An implant retention device is provided to assist in restraining movement of a nuclear implant and to assist in preventing expulsion of the nuclear implant through an incision portal or defect in the annular wall. In general, the implant retention device blocks or obstructs at least a portion of an opening in the annular wall, thereby keeping the implant from exiting the nuclear space through the annular opening. In one form, the implant retention device comprises an expulsion prevention member positioned adjacent the nuclear implant and configured to transition between a compressed position and an expanded position. In another form, the implant retention device may comprise a mounting portion to be positioned adjacent one of the vertebral bodies, a blocking portion for at least partially obstructing the annular opening, and an end projection at a terminal end of the blocking portion to resist expulsion of the implant through the annular opening. In yet another form, the implant retention device may include an elongate blocking member having annulus connector portions extending from each side of the blocking member for engaging with an annular wall.